Stitch



July 11, 1933. w 1,917,412

STITCH Filed Oct. 26, 1932 DIRECTION OF SUCCESSIVE STITCH FORMATION.

IN V EN TOR.

Patented July 11, 1933 UNITED STATES PATENT OFFICE LAURENT H. OF AUDUBON, NEW JERSEY, ASSiGNOR TO THE IETBDPOLITAN SEWING MACHINE CORPORATION, OE MACK,

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NEW YORK, A CORPORATION OF DELA- STITCH Application filed October 26, 1982. Serial No. 839,565.

This invention. relates to an improvement in stitches, the object of the invention being to provide a strong, elastic and. durable stitch that may he made at high speed and be suitable for a great variety of sewed articles, especially for the seaming of pants and coats thatare subject to considerable strain and frequently break and rip.

The crotch seams of pants, sleeve seams, and the back seams of coats give way unless double stitched tomake such seams secure. This double stitching means two operations and even then the sewed lines are not uniiorm or even, so that the two lines of stitches do not equally share in strength because they are not united so as to hold together, consequently, they break, pull out and the seam 0 This improved stitch overcomes these objections because the needle threads pass through the material side by side i. e. sub stantially contiguous in staggeredor alternate relation andthese needle threads are concatenated with a sin 1e looper thread in such a way as to provide ull strength of the seam equal to the full strength of the material, and such seams will open and lie fiat when pressed without showing any ridge after pressing.

Another advantage is that this improved stitch can be made on machines now in use by slight changes in their stitching mechanism, such as the addition of another needle to a single needle machine, means for properly controllingthe second needle thread, the provision of needle clearance in the presser foot and throat plate, and a timed relation of the thread carrying looper to co-act with two needles, one behind the other, thus enabling the production of this improved stitch on the machines now in use, especially the wellhnown liletropolitan sewing machine, in which the looper operates in a path opposed to the direction of the feed of the work. it. "further advantage of the present invention resides in the fact that the sewing machine is operated at normal speed to produce twice the work of the usual machine, that is each reciprocation of the needle her produces two stitches.

This improved stitch has proved to havetwice the strength of the single needle United States standard stitch type 401, and the lineal yardage of stitching is twice'that of the machine making such type of stitch because the length of stitch or feed stroke can be double that of such old machine.

In the drawing accompanying and forming a part of this specification, Fig. l is a view of this improved stitch enlarged to clearly show the concatenation ofthe threads.

Fig. 2 shows the stitch more closely formed.

Fig. 3 is a top viewand illustrates so having both short and long needle thread stitches. l I

Fig. 4.- is a bottom view of the stitch with the needle loops close together, and

Fl 5 is a modified form of stitch showing a di erent needle loop spacing.

Fig. Sillustrates a seam showing the top and bottom of the work and stitch,

' Similar characters of reference indicate corresponding parts in the several views.

Before explainin in detail the present improvement and mo 0 of operation thereof, I desire to have itunderstoodthat the invention is not limited to the details of construction and arrangement of parts illustrated in the accompanying drawing since'the inven-' tion is capable of other embodiments, and thatthe phraseology which I employ is for the purpose of description and not of limitation.

This improved stitch is made with two substantially contiguousneedle threads 1 and 2 as shown in Figure 3 and a single looper thread 6 and these two needle threads are carried through the material by the needles to form needle loops 3 and 4, located in substantial alignment on the under side of the work while the needle stitches l and 2 on top of the work are located in alternation or staggered.

ach pair of needle loops passes through a loop 5 of: the looper thread extending from the last preceding stitch and this looper thread loop, in turn, passes througha pair of preceding needle loops 3 and 4c of the needle threads and 2 and extends one stitch will length. Thus, a looper loop passes through a pair of needle loops and, in turn, receives a pair of needle loops so that each pair of needle loops not only has extending there- 5 through a looper loop but also passes through another looper loop, the ioregoing operations being repeated to form a sequence of stitches.

. The needle lops 3 and l on the under or m looper side of the work are in tandem relation or as closely in line as possible, spaced with relation to the direction of the feed of the material with respect to the length of the stitch. That is to say, if the length of the stitch he one-quarter inch and the needles place the loops 3 and d one-eighth inch apart, then eight stitches per inch will he placed in the material. This improved stitch also permits diii'erent spacing of the needle loops 3 and l If spaced one-sixteenth of an inch apart, the loops will-he that distance from one another regardless of the length oi? stitch.' Figs. 4 and 5 illustrate this difference of needle loop spacing.

Looking at the bottomol the stitch on the material 7, it will be seen that this improved stitch provides a secure anchorage even with the very finest of threads so that a flat smooth stitch is produced with the needle thread loops 3 and drawn well into the material. This improved stitch has greater elasticity and holding power and strength than United States standard stitch type 401 even if that stitch is produced with threads equal in hulk o'r size to the three threads used in my improved stitch.

Fig. 6 illustrates the improved stitch applied to material 8 having a pinhed trimmed edge 9. The material is folded over to show hoth top and bottom of the stitch and seam. The arrangement of the tandem needle loops with respect to the direction of the feed of the material may he each as to place the loops 3 and t in a line whereby the threads =1 extending from one stitch tothe next will he over one another or nearly so. The loops 3 and l may also he placed with slight-lateral spacing, in which case there will he a space between the threads 1 and 2 lying on the top 543 surface of the material 7.

It the spacing of the. needles is equal to one-hall the length of the feed stroke, then the needle loop of one of the needles will he placed mid-way between two of, the needle loops of the other needle, alternating in this manner so that the spacing or the needle loops on the hottom of the work will he equaldistances from one another (see Fig. i) On the other hand, by varying the spacing or" ill) the needles, the stitch may he lengthened or shortened; difierence is shown in Figs. 4. and 5.

In this" improved stitch, as clearly shown in Figs. 1 and 2, each group of four needle 65 loops, two loops 3 and two loops 4, complete loop 3.

To complete the stitch requires two cycles of sewing machine movements. That is to say, starting the cycle with the needles at their lowest position where they have formed the first two loops 3 and {l at the right hand of Fig. 1, the looper thread 6 passes through these two loops as'the needles rise. When they have moved clear above the work, the feed of the material advances. Then the needles descend through the material to form the second pair of loops 3 and d and as the needles thus descend with these loops of needle thread, they are passed throu h the left hand end of the first looper threa loop. The looper moves backward out oi the first two loops of needle threads 3 and 4 and then again moves forward through the second pair of needle loops 3 and t to form the next looper thread loop and soon. fhe movements are repeated for succemive stitches.

It will be clearly understood that in the formation of this improved stitch, the looper thread is anchored to the bottom of the work by each group of fourneedle loops, whereby a stronger stitch with greater elasticity is produccd,-and the oiltput of a machine arranged to make this improved stitch is twice as much as that of the ordinary machine.-

As before stated, this new stitch makes a very satisfactory seam :t'or ants and coats. It also is very satisfactory :tor the stitching of shoes, dresses and especially those made from delicate fabrics, and is also very satisfactory for hag stitching for it is an advantags in the seam structures of bags used for fine granular materials such as sugar, salt and the like in that it produces a seam that is less liable to leakage since the needle threads pam in tandem loop formation through the material side by side in sta gered or alternate relation and these nee e threads are concamnated in the direction of the stitch formation with a single looper thread in such a way as to provide full strength of the seam equal to the full strength of the material. Such seams are thus less liable to leakage if used for bags or similar articles and odor a very strong, elastic seam for delicate fahrics used for wearing apparel. These seams will also open and lie flat when presed without showin any stitch ridge marking after pressing us to the fact that only one looper thread is used and it is drawn fiat against the material where it lies smoothly so that in the operation of pressing the ill? Elli.

llll.

garments, it will not form a ridge and show through on the right side of the material. 190

It is to be understood that, by describing in detail herein any particular form, structure or arrangement, it is not intended to limit the invention beyond the terms of the several claims or the requirements of the prior art.

Having thus explained the nature of my said invention and described a way of constructing and using the same although without attempting to set forth all of the formsin which it may be made, or all of the modes of its use, I claim:

1. An improved stitch comprising a pair of parallel contiguous rows of needle stitches located in alternation on top of the work with the needle loops on the under side of the work in tandem relation, and a looper loosprojecting through a pair of needle loops an through which looper loop a pair of needle loops pass.

2. An im roved stitch comprising concatenated nee lc loops and looper loops, the needle loops being located in tandem relation on one side of the work and the stitches there of contiguous and in alternation on the oppo site side of the work, each pair of needle loops receiving therethrough a looper loop, and another looper loop receiving therethrough the same pair of needle loops.

and located in alternation on one side of the material and having the loops thereof in tandem relation in the direction of the stitch formation on the opposite side of the material and a looper thread, the loops passing through and also around the needle thread loops to anchor the stitches to the material.

5. An improved three thread stitch in which alternatin needle thread loops pass through the matenal forming contiguous stitches on one side thereof and are anchored on the other side of the material by a looper thread passing forwardly through two of the said needle.

loops and then forwardly around the next two needle loops.

Signed at Philadelphia, Pennsylvania, this 10th day of October, 1932.

- LAURENT H. WILD. 

